One of the problems that occurs in the operation of automobiles is that, where an automatic floor transmission shifter is provided, it is possible to remove the ignition key even when the transmission is not in park position.
Accordingly, among the objectives of the present invention are to provide a key interlock system that functions between the ignition key lock and the automatic floor mounted transmission shifter to prevent removal of the key from the ignition lock except when the transmission shifter is in parked position; which system is relatively simple and utilizes a minimum number of parts; which system is positive and cannot be bypassed; and which system is low in cost.
In accordance with the invention, a key interlock system for an automatic floor mounted transmission shifter adapted to be used with an ignition key located in the steering column and adapted to translate a key slide actuator upon rotation of the key through a pinion acting on a gear rack on the slide actuator comprises a cable assembly including a conduit fixed at one end adjacent the ignition key and at the other end adjacent the automatic floor mounted transmission shifter. A strand is connected at one end to a spring loaded pawl adjacent the actuator and at the opposite end to a cam plate adjacent the shifter. In the key out position, the pawl engages the key actuator placing the strand in tension so that the shifter is prevented from movement from a park position. When the key is advanced to the start, run or off position the pawl engages a groove in the key actuator allowing the shifter cam plate to be moved from ark position to the desired drive gear position. When the shifter is advanced to a drive position, the shifter cam is held in a position so that the pawl cannot return to a position which will permit the key actuator to move to a key out position due to the engagement of the pawl with the edge of the groove in the key actuator. Upon return of the shifter to park position, the cam plate relieves the tension on the strand so that the pawl will move out of engagement with the edge of a groove in the key actuator, permitting the key to be turned to the key out or accessory positions.